/*
 * Copyright (C) 2011 Cyril Mottier (http://www.cyrilmottier.com)
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package greendroid.image;

import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.graphics.RectF;

/**
 * An {@link ImageProcessor} that masks the given Bitmap according to a shape or
 * another Bitmap.
 * 
 * @author Cyril Mottier
 */
public class MaskImageProcessor implements ImageProcessor {

	private static final int CUSTOM = 1;
	private static final int RECTANGLE = 2;

	private int mShape;
	private float mRadius;
	private float[] mRadiiArray;

	private Bitmap mMaskBitmap;

	private final Paint mMaskPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
	private final Paint mFillPaint = new Paint(Paint.ANTI_ALIAS_FLAG);
	private final Path mPath = new Path();
	private final RectF mRect = new RectF();

	/**
	 * Create a new MaskImageProcessor using a simple rectangle as mask.
	 * Specifying a radius > 0, enable clients to use a rounded rectangle,
	 * rather than a rectangle.
	 * 
	 * @param radius
	 *            The radius for the corners of the rectangle.
	 */
	public MaskImageProcessor(float radius) {
		init();
		mShape = RECTANGLE;
		if (radius < 0) {
			radius = 0;
		}
		mRadius = radius;
	}

	/**
	 * <p>
	 * Create a new MaskImageProcessor using a simple rectangle as mask.
	 * Specifying a radius > 0, enable clients to use a rounded rectangle,
	 * rather than a rectangle.
	 * </p>
	 * <p>
	 * Specify radii for each of the 4 corners. For each corner, the array
	 * contains 2 values, [X_radius, Y_radius]. The corners are ordered
	 * top-left, top-right, bottom-right, bottom-left
	 * </p>
	 * 
	 * @param radii
	 *            The radii for the corners of the rectangle
	 * @see Path#addRoundRect(RectF, float[], android.graphics.Path.Direction)
	 */
	public MaskImageProcessor(float[] radii) {
		init();
		mShape = RECTANGLE;
		mRadiiArray = radii;
		if (radii == null) {
			mRadius = 0;
		}
	}

	/**
	 * <p>
	 * Create a new MaskImageProcessor using the specified Bitmap as mask.
	 * </p>
	 * 
	 * @param maskBitmap
	 *            The Bitmap used for masking
	 */
	public MaskImageProcessor(Bitmap maskBitmap) {
		init();
		mShape = CUSTOM;
		mMaskBitmap = maskBitmap;
	}

	private void init() {
		mFillPaint.setColor(Color.RED);
		mMaskPaint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));
	}

	public Bitmap processImage(Bitmap bitmap) {

		if (bitmap == null) {
			return null;
		}

		final int width = bitmap.getWidth();
		final int height = bitmap.getHeight();

		mRect.set(0, 0, width, height);

		Bitmap result = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888);
		Canvas canvas = new Canvas(result);

		switch (mShape) {
		case CUSTOM:
			canvas.drawBitmap(mMaskBitmap, 0, 0, mFillPaint);
			break;

		case RECTANGLE:
		default:
			if (mRadiiArray != null) {
				mPath.reset();
				mPath.addRoundRect(mRect, mRadiiArray, Path.Direction.CW);
				canvas.drawPath(mPath, mFillPaint);
			} else {
				float rad = mRadius;
				float r = Math.min(width, height) * 0.5f;
				if (rad > r) {
					rad = r;
				}
				canvas.drawRoundRect(mRect, rad, rad, mFillPaint);
			}
			break;
		}

		canvas.drawBitmap(bitmap, 0, 0, mMaskPaint);

		return result;
	}
}
